An ophthalmic surgical microscope system of the kind referred to above is disclosed in German utility model registration 202 15 635 U1. There, a surgical microscope is described which is accommodated in a carriage unit on a stand so as to be adjustable in elevation. For focusing, the surgical microscope can be moved up and down in the carriage unit via a drive unit in the form of an adjusting knob. An ophthalmic ancillary module is mounted in front of the microscope main objective system of the surgical microscope. The ancillary module can be pivoted into and out of the viewing beam paths. The ophthalmic ancillary module is mounted on the surgical microscope. The ophthalmic ancillary module carries an ophthalmic magnifier lens which is adjustable in elevation. A drive is provided for adjusting the ophthalmic magnifier lens and this drive includes a threaded spindle with a drive motor. The ophthalmic ancillary module is pivoted into the viewing beam paths of the surgical microscope in order to adjust the ophthalmic surgical microscope system for the examination of the ocular fundus of the eye of a patient. The surgical microscope and the ophthalmic magnifier lens are then moved until a sharp image of the ocular fundus can be seen in the binocular tube of the surgical microscope.
The Topcon Company markets an ophthalmic surgical microscope system under the product designation OMS 800 OFFISS and this ophthalmic surgical microscope system includes a surgical microscope having an ophthalmic ancillary module. The surgical microscope is accommodated on a stand unit so as to be adjustable in elevation. The ophthalmic ancillary module is mounted on this stand unit separately from the surgical microscope. The ophthalmic ancillary module includes an ophthalmic magnifier lens which can be pivoted into and out of viewing beam paths in front of the main objective system of the surgical microscope. The separate accommodation of the surgical microscope and the ophthalmic ancillary module on the stand unit permits the focusing of the surgical microscope in that the surgical microscope is moved up or down without, at the same time, changing the position of the ophthalmic magnifier lens.